Centrifugal governor for controlling the rpm of injection type internal combustion engines

ABSTRACT

A centrifugal governor for controlling the rpm of an injection type internal combustion engine, having a regulating member which is adjustable dependent on the rpm and adapted to have its regulating displacements transmitted to the fuel delivery control means of an injection pump of the engine via at least one intermediary lever, while the regulating member acts upon a force-transmitting lever which is pivotally mounted in a housing of the governor and which is supported on an adjustable abutment means fixedly provided in said housing, and is biassed by means of a regulator spring being attached, at its one end, to a first spring seat in the governor housing and engaging, at its other end, a second spring seat provided at the force-transmitting lever, is improved by providing a bearing bolt rotatably mounted in the governor housing and having a helicoidal groove serving as the said first seat of the regulator spring, while the second seat of said regulator spring is adjustable, thereby rendering the bias of the regulator spring relative to the forcetransmitting lever variable.

' llite States Patent 1191 eelistein etal. 1 ct. 22, 1974 CENTRIFUGAL GOVERNOR FOR 3,714,935 2/1973 Dreisin 123/140 R CQNTROLLING H M 0 INJECTION 3,759,236 9/1973 Staudt et a1. 123/140 R TYPE INTERNAL COMBUSTION ENGINES [75] Inventors: Herbert Bechstein, Esslingen;

. Eberhard Hofmann, Kirchberg,

MPH; Hans-Ji Jae Ditzingen; Rolf Miiller, Stuttgart-Freiberg; Ernst Ritter, Stuttgart; Heinrich Staudt, Ma m nsm-T ha s m all of Germany [73] Assignee: Robert Bosch GmbH, Stuttgart,

Germany [22] Filed: May 21, 1973 [21] Appl. No.: 362,303

[30] Foreign Application Priority Data Primary Examiner.Laurence M. Goodridge Assistant Examiner-Cort Flint Attorney, Agent, or FirmEdwin E. Greigg [5 7] ABSTRACT A centrifugal governor for controlling the rpm of an injection type internal combustion engine, having a regulating member which is adjustable dependent on the rpm and adapted to have its regulating displacements transmitted to the fuel delivery control means of an injection pump of the engine via at least one intermediary lever, while the regulating member acts upon a force-transmitting lever which is pivotally mounted in a housing of the governor and which is supported on an adjustable abutment means fixedly provided in said housing, and is biassed by means of a regulator-spring being attached, at its one end, to a first spring seat inthe governor housing and engaging, at its other end, a second spring seat provided at the force-transmitting lever, is improved by providing a bearing bolt rotatably mounted in the governor housing and having a helicoidal groove serving as the said first seat of the regulator spring, while the second seat of said regulator spring is adjustable, thereby rendering the bias of the regulator spring relative to the force-transmitting lever variable.

5 Claims, 3 Drawing Figures PAIENIEMMW SHEET 1 of 3 Fig. 1

. 1 CENTRIFUGAL GOVERNOR FOR CONTROLLING THE RPM OF INJECTION TYPE INTERNAL COMBUSTION ENGINES BACKGROUND OF THE INVENTION The invention relates to a centrifugal governor for controlling the rpmof injection type internal combustion engines, having a regulating member which is adjustable dependent on the rpm, and adapted to have its regulating displacements transmitted to the fuel delivery'control means of an injection pump of the engine via at least one intermediary lever, while said member acts upon a force-transmitting lever which is pivotally mounted in a housing of the governor and which is supported on an adjudtable abutment means fixedlyprovided in the housing, and is biassed by means of a regulator spring devised as a tension spring, which spring is attached at its one end to a first spring seat inthe governor housing and which engages, at its other end, a second spring seat provided at the aforesaid forcetransmitting lever.

In a known centrifugal governor of this type, for controlling the rpm, the regulator spring of which is fixedly hooked up in the governor housing and engages the force-transmitting lever via a connecting rod, the initial bias of the regulating spring can be varied, for the purpose of adjusting the rpm, by the displacement of an adjusting nut which is supported at the forcetransmitting lever via a pressure plate. In order to change the proportional range, the position of the pressure plate on the force-transmitting lever can be shifted, by means of notches being provided on the two parts, in such a manner that the direction of action of the regulator spring changes. However, this adjustment can only be effected in stages, the size of which is determined by the distance of the notches from each other. A further drawback resides in the considerable amount of energy needed to lift the pressure plate over the notches, which also results in a change in the position of the connecting rod and its associated adjusting nut. Both last-mentioned disadvantages moreover make the use of an automated adjuster impossible; moreover, the governor must be arrested during every adjustment of its proportional range.

OBJECT AND GENERAL DESCRIPTION OF THE INVENTION It is, therefore, an object of this invention to provide an improved centrifugal governor of the aforementioned type for controlling the rpm which is free from the above-described disadvantages and which permits continuous adjustment thereof even during operation.

This object is attained in accordance with the invention by the improvement, in the governor of the aforementioned type comprising a first spring seat of the regulator spring in the form of a helicoidal groove which seat is machined in a bearing bolt mounted in the governor housing and rotatable for adjusting the proportional range of the governor, thereby changing the direction of action of the regulator spring, while the second seat of the regulator spring is adjustable to cause an adjustment of the initial bias of the regulating spring relative to the force-transmitting lever in order to determine the rpm to be regulated. Thereby, it becomes possible to adjust continuously the rpm to be regulated,

as well as the proportional range while the governor is in operation. This has the further advantage that the mounting position of both adjusting members does not lever, whereas the other lever arm of the angle lever is supported on an abutment screw which is screwed into the force-transmitting lever and which can be adjusted for setting the rpm to be regulated.

In order to further improve the adjustability of the governor, as a particularly advantageous feature of the rpm-regulating governor according to the invention,

the regulator spring and the force-transmitting lever,-

being devised as .a straight bar lever, are arranged at least-approximately perpendicular to the axis of the regulator sleeve, with the one lever arm of the angle lever projecting perpendicularly away from the forcetransmitting lever, while the bearing bolt, as well as the stop screw are arranged in parallel with the axis of the regulator sleeve. In this arrangement all adjustable members are accessible from one side, namely, from the one front end of the governor, whereby, as a particular advantage, the use of a single adjusting tool combining in one unit the adjusting means for all adjustable members is made possible.

The invention will be better understood and further objects and advantages will become apparent from the ensuing detailed specification of preferred but merely exemplary embodiments taken in conjunction with the drawings.

DETAILED DESCRIPTION OF THE DRAWINGS FIG. 1 represents a longitudinal sectional view of a preferred embodiment of the governor according to the invention taken in a plane along line II in FIG. 2;

FIG. 2 is a cross-sectional view of the same embodiment taken along line II-ll in FIG. I; and

FIG. 3 is a longitudinal sectional view taken along line lII-III in FIG. 2.

DETAILED DESCRIPTION OF THE EMBODIMENT To the drive shaft 10 of a fuel injection pump (not shown) of an internal combustion engine, there is secured a flyweight governor 11 comprising pivotally mounted flyweights 12 having (radially inwardly) extending arms 13 which engage the frontal face 14 of a thrust bearing 16 which latter engages an abutment on a regulator sleeve 15 serving as the regulating member, and which bearing 16 transmits the adjusting forces of the flyweights 12 to the regulator sleeve 15. The regulator sleeve 15 is supported at its one end on a cylindrical pin 17 of the drive shaft 10 and its other end, facing away from drive shaft 10, is provided with laterally projecting guiding pegs 18 each of which is guidingly inserted in a guide track 19 formed as a recess in a forcetransmitting lever 21 (see FIG. 3).

The force-transmitting lever 21 is of substantially U- or H-shaped cross section, the shanks of the U being formed by two flat lever sidewalls or legs 22 projecting on the side of the lever facing toward the injection pump and disposed in parallel with one another; these legs 22 are provided with guiding recesses 19 in which the guide peg 18 of the regulator sleeve 15 is inserted. At the level of the axis of the drive shaft and the regulator sleeve 15, an adjusting member 23 is screwed into the force-transmitting lever 21 and is secured in its set position by means of a nut 24. The adjusting member 23 has a plane face 26 against which a convex front end 27 of the regulator sleeve abuts after traversing a first part a of its travel path.

While traversing the aforesaid first path a, the regulator sleeve 15 acts upon a leaf spring 28 serving either as a starting control spring or as a no-load control spring. One end of spring 28 is supported in forcetransmitting lever 21, and the other end 31 thereof exerts pressure against the guide pegs 18 of regulator sleeve 15. The bias of the leaf spring 28 acting on regulator sleeve 15 is generated by an adjusting screw 34 which is screwed into force-transmitting lever 21 and which is secured in its set position by means of a nut 35. The force-transmitting lever 21 is a straight two-armed lever having as pivot a bearing pin 38 which is stationary in the governor housing 37; lever 21 is shown in its neutral, vertically disposed position which latter is determined by an abutment 39 which is fixed in governor casing 37 and which is constituted by a self-locking abutment screw 41 which is screwed into casing 37.

The force-transmitting lever 21 can be swivelled counter-clockwise about bearing pin 38. The swivelling motion occurs when the forces, generated by the flyweights 12 and transmitted from the regulator sleeve 15 via the adjusting member 23 to the forcetransmitting lever 21, are larger than the resetting force generated by a regulator spring 42. This regulator spring 42 is a tension spring'which is arranged in the governor substantially perpendicularly to the axis of regulator sleeve 15 and which is attached at two spring seat counterforce bearings 43 and 44 of which the first bearing 43 is fast in casing 37 while the second bearing 44 is arranged on lever arm 45a of an angle lever 45 which serves for adjustment of the maximal rpm. Angle lever 45 is connected to force-transmitting lever 21 by means of a pivoting pin 46 inserted into openings opposite one another in the two parallel legs 22 of lever 21. The position of the angle lever 45 illustrated in the drawings, wherein one lever arm 45a of lever 45 projects at right angle out of the force-transmitting lever 21, is determined by means of an adjusting screw 47 which serves to adjust the bias of the regulator spring 42 and against which the other lever arm 45b of angle lever 45 abuts. This bias of the regulator spring 42 determines in a known manner the maximum rpm which the governor is to regulate or limit.

The first spring seat 43 of the regulator spring 42 is machined as a helicoidal groove 48 of semicircular pro-* file into a bearing bolt 49 which latter is mounted in the governor housing 3 in a position parallel with the axis of the regulator sleeve 15, as well as in parallel with the stop screw 41 and at least approximately in parallel with the adjusting screws 34 and 47 and with the adjusting member 23.

The bearing bolt 49 can be rotated for changing of the proportional range of the governor as, during such rotation of the bearing bolt 49, the suspension point, i.e., the location of the first spring seat 43, of the regulator spring 42 is shifted horizontally in such a manner that the direction in which the spring 42 acts, is changed. As is known, the effective rigidity of the spring thereby changes with regard to the force exerted on the force-transmitting lever 21, which force counteracts, as resetting force, the controlling force of the regulator sleeve 15.

In order that the position of the bearing bolt 49 does not change while the governor is in operation, a pressure screw 51 is screwed into the governor housing in a known manner, slightly eccentrically of the central axis of bearing bolt 49 in the vicinity of one of the bearings of the said bolt 49. (see FIG. 3).

The regulator sleeve 15, while working against the resetting forces of the regulator springs 28 and 42, transmits its adjusting forces via an intermediary swivel lever 53 and a cam lever 54, serving as a second swivel lever, as well as via an accumulator 55, to an actuating rod 56 serving as the fuel delivery control rod of the injection pump, (FIG. 3).

The swivel lever 53 is in the form of a U-shaped stirrup and is mounted in the governor housing 37 by means of two ball and socket mountings 62 (see FIG. 2 for this detail) which are linked by means of a pin 63 to the cam lever 54. The linkage between the regulator sleeve 15 and the swivel lever 53 is formed by a ball joint 57 (FIG. 1), one part of which is secured to a bearing arm 61 of the regulator sleeve 15. The cam lever 54 is provided with a connecting link guide 64 (FIG. 3), which is engaged by a guide pin 65 of a steering lever 66 which is fixedly connected with a shaft 67 supported in governor housing 37. An operating lever 68 (FIG. 2) is secured to this shaft 67 outside the governor housing 37, whereby the shaft 67, and thus the steering lever 66, can be swivelled, and, whereby, at the same time, the position of the actuating rod 56 and together therewith the lever transmission ratio of the twoarmed cam lever 54 can be changed in a manner known per se. The cam lever 54 and the accumulator 55 are linked by a connecting pin 69 (FIG. 3), and the shaft 67 (see FIG. 2 for this detail), which carries at its one end, outside the governor housing 37, the operating lever 68, is provided at its other end with a stop lever 71 for limiting the pivoting angle of the operating lever 68 and thereby that of the steering lever 66 in conjunction with known stop means (not illustrated). Both levers 68 and 71 can, of course, also be arranged on the same side of the governor.

The governor housing 37 is closed by means of a cover 78 on the frontal face thereof away from the injection pump, which cover allows, after its removal, access to all essentially horizontally disposed adjusting members of the governor. These adjusting members are, to summarize them again, the bearing bolt 49 for adjusting the proportional range of the governor, the stop screw 41 for adjustment of the neutral position of the force-transmitting lever 21, the adjusting screw 34 for changing the bias of the no -load regulator spring 28, and the adjusting member 23 for the adjustment of the first partial travel a of the regulator sleeve 15, which travel a is normally identical with the idling stroke of the regulator sleeve 15.

OPERATION OF THE EMBODIMENT The governor operates as follows: The movable parts of the governor are illustrated in neutral or rest position (the number of revolutions per minute (rpm) is zero); the operating lever 68 and together therewith the steering lever 66 are in their rest position.

For starting the internal combustion engine, the operating lever 68 together with the steering lever 66 (see P16. 3 for this detail) are brought into full-load position by swivelling in the direction of the arrow 79, which results in shifting of the actuating rod 56 by means of the cam lever 54 and by way of the accumulator 55 in the direction of the arrow 80 into the starting position. In the starting position of the actuating rod 56, the injection pump delivers a quantity of fuel to the internal combustion engine, which is in excess of the fuel quantity required for full-load operation, which excess facilitates the starting of the engine.

After the engine has been started, and while the operating lever 68 is, for instance, being kept in the full load position, the-rpm rises further and the centrifugal flyweights 12 swing outwardly, under the influence of centrifugal forces, from their position as shown in the drawing. By means of their arms 13, the centrifugal flyweights 12 exert pressure via the thrust collar 14 and the thrust bearing 16 on the regulator sleeve 15, which latter is thereby displaced against the force of the noload control leaf spring 28 until it abuts with its front face 27 at the end plane 26 of the adjusting member 23 which is screw-fitted into the force-transmitting lever 21. This displacement of the regulator sleeve by the partial travel path a causes the bearing arm 61 with the ball joint 57 to be displaced by the same length of travel, and the actuating rod 56 is shifted by means of the linkage members 53, 54 and 55 from the starting position into the full-load position. The governor remains in this position as the rpm increases further until that final rpm is attained, which is predetermined by the bias of the regulator spring 42. If this final rpm is exceeded in the case of the engine operating under partial load, the force-transmitting lever 21 lifts off its abutment 39 against stop screw 41 due to the increasing pressure exerted on lever 21 by the regulator sleeve 15, and the latter travels further beyond the distance a. The regulator sleeve 15 thereby moves the linkage members 53, 54, 55, and the actuating rod 56 into a position in which the fuel quantity of the injection pump is decreased until it corresponds to the power output of the engine and until the rpm is maintained within the proportional range. As the forces of the governor spring 42 are taken up, on the one hand, by the first bearing 43, and, on the other hand, by the abutment 39 of the force-transmitting lever 21 or by the governor sleeve 15, the linkage members 53, 54, and 55 are free from restoring forces in all operating conditions. If, for example, the actuating rod 56 in its end position rests against an abutment 82, and if the operating lever 68 of the governor moves beyond a setting corresponding with the abutment 82, a spring of the accumulator 55 is compressed, and only these comparatively small forces are transmitted to the linkage members.

Due to the fact that, as has been mentioned hereinbefore, all adjusting members are accessible from the one front end of the governor, and since they are all arranged in parallel or at least approximately in parallel with one another, the centrifugal rpm-regulating governor according to this invention is particularly suited for an automated setting. But even without such automated setting,the centrifugal governor according to the invention offersthe advantage that all adjusting members are accessible from one end only, and that they can be adjusted independently of one another, i.e., without influencing the function of other adjusting members. A further advantage of this governor resides in the fact that the leaf spring 28, serving as a starting or no-load regulator spring, is supported together with its associated adjusting screw 34 at the forcetransmitting lever 21, whereby, upon abutment of the front face 27 of the regulator sleeve 15 on the supporting lever 21, or at its adjusting member 23, this leaf spring 28 is fixedly clamped, so that it no longer has any influence on the regulation of the final rpm.

What is claimed is:

1. In a centrifugal governor for controlling the rpm of an injection type internal combustion engine, having a regulating member which is adjustable dependent on the rpm and adapted to have its regulating displacements transmitted to the fuel delivery control means of an injection pump of said engine via at least one intermediary lever, while said'member acts upon a forcetransmitting lever which is pivotally mounted in a housing of said governor and which is supported on an adjustable abutment means fixedly provided in said housing, and is biassed by means of a regulator tension spring being attached, at its one end, to a first spring seat in said governor housing and engaging, at its other end, a second spring seat provided at said forcetransmitting lever, the improvement comprising a bearing bolt rotatably mounted in said governor housing and having a helicoidal groove serving as said first seat of said regulator tension spring, said second seat of said regulator tension spring being adjustable, thereby rendering the bias of said regulator tension spring relative to said forcetransmitting lever variable.

2. The improvement as described in claim 1, wherein said helicoidal groove in said bearing bolt is of semicircular cross section.

3. The improvement as described in claim 1, further comprising an angle lever, having said second seat of said regulator tension spring arranged on one lever arm thereof, said angle lever arm being pivotally mounted on said force-transmitting lever; and an adjusting screw being screw-connected to said force-transmitting lever and adapted for setting the rpm to be regulated, the other arm of said angle lever being supported on said adjusting screw.

4. The improvement as described in claim 3, wherein said force-transmitting lever is a straight bar lever, said straight bar lever and said regulator tension spring extending at approximately a right angle with the axis of said regulating member.

5. The improvement as described in claim 4, wherein said one lever arm of said angle lever projects substantially at a right angle from said force-transmitting lever, and said bearing bolt as well as said adjusting screw are disposed in parallel with the axis of said regulating member. 

1. In a centrifugal governor for controlling the rpm of an injection type internal combustion engine, having a regulating member which is adjustable dependent on the rpm and adapted to have its regulating displacements transmitted to the fuel delivery control means of an injection pump of said engine via at least one intermediary lever, while said member acts upon a force-transmitting lever which is pivotally mounted in a housing of said governor and which is supported on an adjustable abutment means fixedly provided in said housing, and is biassed by means of a regulator tension spring being attached, at its one end, to a first spring seat in said governor housing and engaging, at its other end, a second spring seat provided at said forcetransmitting lever, the improvement comprising a bearing bolt rotatably mounted in said governor housing and having a helicoidal groove serving as said first seat of said regulator tension spring, said second seat of said regulator tension spring being adjustable, thereby rendering the bias of said regulator tension spring relative to said forcetransmitting lever variable.
 2. The improvement as described in claim 1, wherein said helicoidal groove in said bearing bolt is of semicircular cross section.
 3. The improvement as described in claim 1, further comprising an angle lever, having said second seat of said regulator tension spring arranged on one lever arm thereof, said angle lever arm being pivotally mounted on said force-transmitting lever; and an adjusting screw being screw-connected to said force-transmitting lever and adapted for setting the rpm to be regulated, the other arm of said angle lever being supported on said adjusting screw.
 4. The improvement as described in claim 3, wherein said force-transmitting lever is a straight bar lever, said straight bar lever and said regulator tension spring extending at approximately a right angle with the axis of said regulating member.
 5. The improvement as described in claim 4, wherein said one lever arm of said angle lever projects substantially at a right angle from said force-transmitting lever, and said bearing bolt as well as said adjusting screw are disposed in parallel with the axis of said regulating member. 